Electrochemical performance of Sn4P3 negative electrode for Na-ion batteries in ether-substituted ionic liquid electrolyte

We have previously disclosed that the ionic-liquid electrolyte sodium bis(fluorosulfonyl)amide (NaFSA)/1-methyl-1-propylpyrrolidinium bis(fluorosulfonyl)amide (Py13-FSA) can significantly improve the cycling stability of Sn4P3 negative electrodes for Na-ion batteries (NIBs). However, the strong electrostatic interaction between Na+ and FSA− in the electrolyte leads to high viscosity and low conductivity. In this study, we have tried to improve the conductivity of the electrolyte and enhance the rate capability of the Sn4P3 electrode by introducing an ether group in the side-chain of the ionic liquid cation to reduce said electrostatic interaction. Ether-substituted ionic liquid 1-methoxymethyl-1-methylpyrrolidinium (PyMOM)-FSA showed higher conductivity than Py13-FSA and the Sn4P3 electrode exhibited a higher rate capability. The differential capacity vs. potential plots suggest that the reaction between Na+ and Sn or P is promoted in the ether-substituted ionic liquid electrolyte. These results demonstrate that introduction of an ether moiety is an effective approach to improve the rate capability of the Sn4P3 electrode in NIBs

Health improvement framework for actionable treatment planning using a surrogate Bayesian model

効果的な健康改善プランを提案するAIを開発 --個別化医療における健康介入への活用に期待--. 京都大学プレスリリース. 2021-05-28.Clinical decision-making regarding treatments based on personal characteristics leads to effective health improvements. Machine learning (ML) has been the primary concern of diagnosis support according to comprehensive patient information. A prominent issue is the development of objective treatment processes in clinical situations. This study proposes a framework to plan treatment processes in a data-driven manner. A key point of the framework is the evaluation of the actionability for personal health improvements by using a surrogate Bayesian model in addition to a high-performance nonlinear ML model. We first evaluate the framework from the viewpoint of its methodology using a synthetic dataset. Subsequently, the framework is applied to an actual health checkup dataset comprising data from 3132 participants, to lower systolic blood pressure and risk of chronic kidney disease at the individual level. We confirm that the computed treatment processes are actionable and consistent with clinical knowledge for improving these values. We also show that the improvement processes presented by the framework can be clinically informative. These results demonstrate that our framework can contribute toward decision-making in the medical field, providing clinicians with deeper insights

Piperidinium-Based Ionic Liquids as an Electrolyte Solvent for Li-Ion Batteries: Effect of Number and Position of Oxygen Atom in Cation Side Chain on Electrolyte Property

ArticleJournal of The Electrochemical Society. 167(7): 174101 (2019)journal articl

Fluorescence and chemiluminescence behavior of distyrylbenzene bearing two arms of dipicolylaminomethyl groups: Interactions with zinc ion and ATP

Available online 31 January 2018.The absorption and fluorescence spectral study of the distyrylbenzene bearing two arms of the dipicolylaminomethyl groups, the effective ligands for Zn2+, was studied in the presence of Zn2+ and ATP. Upon complexation of the distyrylbenzene with zinc ions in acetonitrile, enhancement of the fluorescence intensity was observed due to inhibition of intramolecular PET (photo-induced electron transfer) quenching, but no effect was found in aqueous media because the equilibrium laid to the free form of the ligands. In contrast, the addition of ATP disodium salt was effective to enhance the fluorescence intensity of the combination of the distyrylbenzne and Zn2+ in aqueous media. This assembly was applied to the peroxyoxalate chemiluminescence system and a significant increase in the intensity was observed, which provides a potential detection for ATP by chemiluminescence. (C) 2018 Elsevier B.V. All rights reserved.ArticleSPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY. 195:223-229 (2018)journal articl

Influence of the structure of the anion in an ionic liquid electrolyte on the electrochemical performance of a silicon negative electrode for a lithium-ion battery

We investigated the influence of the anions in ionic liquid electrolytes on the electrochemical performance of a silicon (Si) negative electrode for a lithium-ion battery. While the electrode exhibited poor cycle stability in tetrafluoroborate-based and propylene carbonate-based electrolytes, better cycle performance was achieved in bis(fluorosulfonyl)amide (FSA–)- and bis(trifluoromethanesulfonyl)amide (TFSA–)-based electrolytes, in which the discharge capacity of a Si electrode was more than 1000 mA h g–1 at the 100th cycle. It is considered that a surface film derived from FSA–- and TFSA–-based electrolytes effectively suppressed continuous decomposition of the electrolyte. In a capacity limitation test, a discharge capacity of 1000 mA h g–1 was maintained even after about the 1600th cycle in the FSA–-based electrolyte, which corresponds to a cycle life almost twice as long as that in TFSA–-based electrolyte. This result should be explained by the high structural stability of FSA–-derived surface film. In addition, better rate capability with a discharge capacity of 700 mA h g–1 was obtained at a high current rate of 6 C (21 A g–1) in FSA–-based electrolyte, which was 7-fold higher than that in TFSA–-based electrolyte. These results clarified that FSA–-based ionic liquid electrolyte is the most promising candidate for Si-based negative electrodes